Abrading machine



4, 1942. G. w. JACKSON EI'AL 2,291,629

ABRADING MACHINE Filed July 28, 1941 3 Sheets-Sheet l INVENTORS A118. 4,1942- s. w. JACKSON ETAL 2,

ABRADING MACHINE GEORGE W. JACKgO N WILUAM P. CANNI N6 M 7 INVENTORS ATORNEY Patented Aug. 4, 1942 UNITED STATES PATENT OFFICE ABRADING MACHINEApplication July 28, 1941, Serial No. 404,340

Southbridge, Mass.,

9' Claims.

This invention pertains to surfacing devices and more particularly tohand surfacing machines such as are used in surfacing lenses in theophthalmic industry.

Heretofore, devices of the type described herein employed a means ofinitiating power supply to rotate a lens lap but did not employ abraking method for retarding and stopping the rotation of the lap afterthe driving power was disassociated from the lap. Further, no brakingmechanism was used in conjunction with a power control, such as anelectric switch connected to a motor so that by a single manipulation,the motor controlled switch and braking mechanism would be actuated.

A slinger on a surfacing machine has been used heretofore but saidslinger was in no instanc combined with a pulley or a brake drum surfacein a single unitary mounting.

The present invention combined the desirable features referred tohereinbefore and it is therefore an object of the present invention toprovide a surfacing machine of the class described wherein braking meansare employed to retard and more readily stop the rotation of the lenslap when the driving power is disassociated from the lens lap.

A further object is to provide a manually operable switching mechanismfor cutting off energy to the motor which causes rotation of the lenslap, in combination with a braking mechanism for readily stoppingrotation of the lens lap after the energy is cut off from th lens lapdriving motor.

A further object is to provide a slinger for a surfacing machine, whichslinger has sumcient diameter to provide a greater braking surface toincrease the effectiveness of the braking action.

A further object of the invention is to provide a unitary structure of asurfacing machine and motor in combination with a braking mechanismhaving slinger means located thereabove to prevent undesirable particlesof dirt and dust from falling into the bearings of the lens lap support.

A further object of the invention is to provide a surfacing machine witha unitary member which is in fact a combination pulley, slinger, andbraking surface.

A further object is to provide a more compact, more efiicient surfacingmachine.

Further and other objects may be and may become apparent to thoseskilled in the art from a perusal of the drawings and the annexedspecification, and it is to be understood that the present disclosure isby way of illustration only and it is not intended that the presentdisclosure be regarded as limitations as changes, modifications, andequivalents may be used without departing from the spirit of thesubjoined claims.

In the drawings:

Fig. l is a side view of the complete surfacing machine;

Fig. 2 is an enlarged cross sectional view partly broken away takensubstantially alon lines 22 of Fig. 3 with the unitary combinationslinger-pulley brake drum shown in proper relation into the lens lapspindle.

Fig, 3 is an enlarged plan view partly broken away showing thearrangement of the braking and switching parts of Fig. 2;

Fig. 4 is a sectional view of a modification showing a different brakingmechanism with a driving pulley connected by a belt to a motor;

Fig. 5 is a sectional view of the braking mechanism taken substantiallyalong lines 55 of Fig. 4;

Fig. 6 is a modification of a cam operated switching mechanism takenalong lines 6-6 of Fig.'

Fig. 7 is a further modification partially broken away and shownpartially in cross section by showing the wide diameter slinger inconjunction with a modified braking mechanism.

Fig. 8 is a plan view of the arrangement of the switching and brakingparts of Fig. 7.

Referring to the drawings and more particularly to Fig, l a. surfacingmachine 8 has a pan 9 inserted therein with a movable operating lever l0having a slidable connection I I on the operating lever. A lens blockpin l2 extends downwardly into the pan to engage a lens block. The

operating lever I0 is movably connected to the machine 8 in anyconventional manner. A brake lever l3 extends below the bench top [4 sothat the brake lever l3 may be operated by pressing a knee against theknee pad l5 which in turn operates a brake and electric switch.Referring to Fig. 2, the hand surfacing machine 8 has a supporting framel6 which supports the pan 9.

A combination slinger, pulley, and braking drum are combined in oneelement l6 which will be hereinafter referred to in connection withFigs. 2 and 3 as a slinger. The slinger I6 is mounted on a hub I1 andhas upper and lower ball races, l9 and 20 respectively, with sealingpads 2| and 22 for the upper and lower races. A look nut 23 isthreadedly connected on the threaded end of the stud portion of theslinger and holds the ball races in operative position.

The lower ball race is used for centralizing the stud 24 and providesupward and radial thrust bearings. The upper ball race l9 providesdownward and radial thrust bearings. Both of said bearings engagesuitable shoulders to reretain said ball races in their respectivepositions. A spindle 25 is threadedly connected into the upper portionof the slinger l6 and supports a lap 21 which engages a lens 26, whichlens is secured to a lens block I 3 in any conventional manner. The lap21 extends through an opening in the protrusion 28 in the center of thepan 9.

Referring to Fig. 3 in combination with Fig. 2 a switching and brakingassembly may be seen wherein a shaft 30 is rotatably mounted in journals49 to permit the shaft 30 to move when pressure is applied to the kneepad I5. An adjustable lever arm 3| has an adjusting pin 32 which islocked in position by a nut 33. The adjusting lever is connected to theshaft 30 by means of the screw 34. A brake arm 35 is ivotally connectedto the pin 36 having a braking surface 31 on one end of the brake arm,which braking surface 31 engages a brake drum 38. The opposing end ofthe brake arm is pressed upwardly by a spring 38 which normally keepsthe brake arm out of engagement with the brake drum while the upwardmovement of the brake arm is restricted by the pin 32 of the adjustablelever 3 I A belt 40 is shown in section, which belt engages the grooveof the pulley portion 4| of the slinger.

A unidirectional switch 42 is mounted on a support 43 and is locked inposition by nuts 44. A switch arm 45 is movable within the switch 42 tomake and break the circuit when the switch arm is operated. A spring 46is shown as a resilient member which is connected to one end of theshaft 30 by any suitable means such as the portion 41 which extendsthrough a hole in the shaft and is flared at the end thereof. Anysuitable means may be provided for holding the resilient member orspring 46 with one end thereof in fixed relation to the shaft so thatthe spring extension 48 may resiliently engage the switch arm 45. Thepurpose of the resilient spring member 46 with its extension 48 is topermit a clockwise rotation of the shaft 36 to urge the extension 48against the switch arm 45 to operate the switch in its initial movement,and to permit a continued clockwise rotation of the shaft 30 to causethe pin 32 to depress the brake arm 35 and press the braking surface 31against the brake drum surface 38. After the initial movement of theshaft 30, whereby the switch 42 is operated, the spring 46 will have itsextension 48 bent. In this way, once the switch 42 is actuated bypressing the extension 48 against the switch arm 45, the extension 48will have a tendency to slide over the head of the switch arm.

From the above description of Figs. 2 and 3, it will be seen that duringthe operation of the hand surfacing machine 8 the motor which is housedin the right side of the machine shown in Fig. 1 will cause the belt 48to be moved and revolve the slinger. If any of the dust or lappingcompound gets between the lap and the protruding portion 28 having theopening therein, the lapping compound will fall on the slinger which isrotating, and the lapping compound will be thrown outwardly therefrom bycentrifugal force. A shoulder 48' extends outwardly on the lower portionof the slinger and provides a shield for the belt and. braking surface,to prevent the lapping compound or other undesirable material fromcoming in contact with the pulley groove and the braking surfaces. Theprotective guard 49 houses the switching and braking mechanism so thatno undesirable particles engage the switching and braking mechanism tohinder proper operation thereof.

Referring to Fig. 4 a modificationis shown wherein a hand surfacingmachine 50 is shown having a framework 5| which supports a motor 52having a pulley 53 connected on the shaft thereof to drive a lap pulley54 by means of a belt 55. A tapered spindle 56 has a lens lap 51 on oneend thereof with a slinger 58 connected to the tapered spindle justbelow the lens lap so that rotation of the pulley 54 will 'also causerotation of the slinger 58. A ball race 59 engages the lower portion ofthe shaft 56 and provides a radial thrust bearing therefor. Another ballrace 68 is provided for the upper portion of the tapered spindle and isa radial and axial thrust bearing. A sealing cap 6| is connected bymeans of screws 62 to the hub 63. The sealing cap is an additionalmeansto the slinger for keeping dirt and lapping compound away from the ballbearings in the ball race and may be of felt, leather, or other suitablematerial having a hole therein to permit the spindle to extendtherethrough with the hole of sufficient size to frictionally engage thespindle and provide a suitable bearing surface thereon for excludingdirt and undesirable particles without appreciably retarding therotational effort of the tapered spindle. A braking arm 64 has a shaft65 which is journalled in a bearing 66 and has a brake band 61 whichgrips the hub 68 of the pulley 54.

For a better understanding of the braking and switching mechanism anenlarged view is shown in Fig. 5 wherein the hub 68 has the brake band61 therearound with one portion securely connected to a block 69 byscrews). A camming member 1| is connected by means of screws 12 to theopposing end of the brake band 61 and the camming member 1| is slidableaxially on the shaft 65. The camming member 13 is securely connected tothe shaft 65 by means of a screw such as 14. A collar 15 fits on the endof the shaft 65 and has a pin 16 extending through the collar and theshaft to provide an end bearing which permits the shaft 65 to berotated. When the shaft 65 is rotated the inclined surface of thecamming member 13 will rotate and engage the inclined surface of the cammember 1|. Since the camming member 13 is stationary axially in relationto the shaft 65, the camming member 1| will be forced away from thecamming member 13 and consequently draw the two ends of the brake bandstogether thereby causing the brake band to frictionally engage the hub68 of the pulley 54 causing a braking action to take place.

A cam 11 is shown in an enlarged view in Fig. 6 for engaging a switcharm 18 of a unidirectional switch 18.

When the brake lever 64 is operated as shown by the arrow direction inFig. 6, the shoulder 86 will engage the switch arm 18 causing theunidirectional switch to be actuated. Continued movement of the cam 11will permit the switch arm 18 to ride on the raised portion of the camso that no additional pressure is exerted on the switch arm due tofurther rotation of the cam 11.

Referring to the modification shown in Figs. 4, 5 and 6, it will be seenthat when it is desirable to operate the machine, pressure on the brakelever 64 will cause the cam ll to actuate the switch 19 and start themotor. Thereupon the brake lever is released and the operation of thespindle 8| extending through the central opening in the pan 9. Anelectric motor 82 is connected to the spindle 8| to cause rotationthereof. A slinger 83 is connected to the shaft 8! and held in positionby a screw 84, or other suitable means. A sealing cap 85, made ofleather, metal, or the like, is also provided above the slinger toassist in keeping out the lapping compound and other undesirablematerial. A brake arm 86 is shown in solid lines in its inoperativeposition having a brake shoe 81 which is securely connected to the brakeshoe arm 88. The brake shoe arm is shown as an extension of a lever 89which is connected to the shaft 90. The lever 89 and the brake shoe arm88 are shown in two pieces since, it may be desirable to adjust thebrake shoe arm 88 by means of a pin 88 in relation to the lever 89 sothat the brake shoe may be varied in relation to the brake drum surfaceSI of the slinger 83. A knee pad 94 is shown connected to a shaft 95which extends through a journal 98 and is adjustably connected theretoby a screw 91. The brake lever 88 and certain of its interconnectingparts are shown dotted in its operative position wherein the brake shoe81 is in engagement with the brake drum surface 9|. The enlarged view inFig. 8 shows the brake shoe 8'! connected to the lever 89, which lever89 is connected to the shaft 9|] by means of the journal 89. A cam 11 isshown in engagement with a switch arm of the switch 19. The switch 19 inFig. 8 is a unidirectional switch with the camming surface beingsubstantially the same as shown in Fig. 6.

A unidirectional switch is shown in all instances since it is to beunderstood that a single actuation of the switch will cause the contactsto close and energize the motor while a following single actuation willcause the switch operation to open and deenergize the motor.

The slinger shown in Fig. 7 has a diameter which is appreciably greaterthan the diameter of either of the other slingers shown. The advantagein this particular case is not only to provide a slinger with a brakedrum portion but to provide a brake drum portion so that the increaseddiameter thereof will provide a greater leverage in the braking actionwhich takes place between the shoe and the enlarged diameter slinger.The modification shown in Figs. 7 and 8 concerns particularly thebraking mechanism, but also utilizes a unidirectional switch as is shownin Fig. 6.

The entire invention not only embraces the particular arrangement ofparts in an assembly as shown but it is particularly concerned with thecombination of a lever arm for operating a switching and brakingmechanism.

The preferable assembly and arrangement of parts is presented in Fig. 2having a single machine element which has a combined slinger surface,pulley to receive a driving element, and brake drum surface forengagement with a brake shoe surface such as 31. This particulararrangement is compact and eflicient. The protection guard 49 is shownextending to the combination slinger element and is shown terminatingbelow the umbrella-like or mushroom type pulley protector. It is to beunderstood that the protection guard may extend entirely around andabove the belt while being located below and within the confines of themushroom type slinger element.

The brake band 61 in the application has been set forth as being' fittedaround the hub 68. It is to be understood that the brake band may bemade of any resilient metal so that when the camming members II and 13are disengaged, the resiliency of the brake band 61 will tend to expandand disengage the hub 68. The brake band 61 may be of metal or asuitable fiber, or a combination of a metal and fiber may be used inlieu of a single element brake band.

In Fig. 2, the preferable showing 'of the invention is presented with aunitary member which is referred to in the specification as a slingermember. This unitary member comprises three elements namely, a slinger,a brake drum, and a pulley. It is to be understood that while a singleelement has been fabricated comprising means for performing the threedistinct functions, three separate elements may be used andinterconnected so as to operate as a single element or any two elementsmay be interconnected with the third element so that the three elementsare mechanically secured together to operate as a single unitary member.

While certain specific elements and arrangements of parts are presentedherein, it is to be understood that the disclosure is by way ofillustration only and that other equivalent elements and arrangements ofparts may be utilized without departing from the spirit of the inventionas presented in the subjoined claims.

Having described the invention, we claim:

1. A handsurfacing machine of the class described having a rotatablespindle and a, lap on said spindle, a unitary member on said spindle forrotating said spindle, said unitary member comprising a pulley, aslinger, and a brake drum, driving meansconnected to said pulley, abrake arm pivotally connected to said surfacing machine having a brakeshoe thereon disposed to engage the brake drum, a motor and a switchtherefor. and control means for actuating said motor switch and saidbrake arm by a single manipulation thereof.

2. A hand surfacin machine of the class described having a rotatablespindle and a lap on said spindle and a unitary member on said spindlerevolubly mounted for rotating said spindle, said unitary membercomprising a slinger surface on the upper portion thereof, a pulley, anda brake drum; a brake lever pivotally connected to said hand surfacingmachine having one portion thereof engageable with said brake drum, oneportion of said brake lever being manually operable to cause said brakelever to engage said brake drum, and a motor connected to said pulleyfor rotating said hand surfacin machine.

3. A hand surfacing machine of the class described having a rotatablespindle and a lap on said spindle, pulley means connected to saidspindle to cause rotation thereof, said pulley including a slingerelement and a brake drum, an

electric motor for driving said pulley, a switching mechanism forcontrolling operation of said motor and a braking mechanism having abrake shoe for engaging said brake drum, said braking mechanism beingused for substantially simultaneously operating said switching mechanismwith the braking mechanism.

4. A device of the class described comprising a spindle having a lapthereon and a pulley mounted on said spindle for revolving said spindleand lap, said pulley including a slinger surface located substantiallythereabove and a brake drum, means for rotating said pulley and brakinmeans engageable with said brake drum for retarding movement of saidpulley.

5. A device of the class described having a lap and a motor for causingrotation of said lap, slinger means driven by said motor and locatedbelow said lap, said slinger means having a continuous cylindricalportion forming a brake drum, a brake shoe engageable with saidcylindrical brake drum portion of the slinger, and manually operablelever means for urging said brake shoe against said brake drum.

6. A device of the class described having a lap and a. motor for causingrotation of said lap, slinger means driven by said motor and locatedbelow said lap, said slinger means having a continuous cylindricalportion forming a brake drum, a brake shoe engageable with saidcylindrical brake drum portion of the slinger, manually operable levermeans for urging said brake shoe against said brake drum, and anelectric switch for controlling operation of said motor, said electricswitch being substantially simultaneously operable by actuation of saidmanually operable lever means.

I. A surfacing machine of the class described having a rotatable spindlewith a lap adjacent one end thereof, a pulley mounted on said spindle, amotor connected to said pulley to cause rotation thereof, a slingerconnected to said spindle and disposed below said lap, a brake drumconnected to said pulley, a brake shoe for engagement with said brakedrum, switching means for controlling operation of said motor, andmanually operable lever means for actuating said switching means andsubstantially simultaneously causing said brake shoe to grip said brakedrum.

8. A device'of the class described comprising a freely rotatablespindle, a lap mounted adjacent one end of said spindle, slinger meansdisposed below said lap and connected to said spindle, pulley meanslocated below said slinger means and connected to said spindle, brakingmeans associated with said pulley for retarding movement of saidspindle, an electric motor connected to said pulley for driving saidspindle, switching means for controlling operation of said motor, acontrol lever having camming members thereon for engaging anddisengaging the brake shoe with the brake drum, and means on saidcontrol lever for actuating said switching means, t the end that aninitial movement of the control lever will actuate the switching meansand energize the motor, and after the motor is in operation anotherinitial movement of the control lever will actuate the switching meansand deenergize the motor while continued movement of the control leverin the same direction will cause said camming members to urge the brakeshoe against the brake drum.

9. A device of the class described having a rotatable spindle havin alap thereon and a pulley mounted for revolving said spindle and lap,said pulley having a slinger located thereabove and a brake drum, motormeans for rotating the pulley, braking means engageable with said brakedrum for retarding movement of said pulley, switching means forcontrolling energization of said motor means, and lever operable meansfor substantially simultaneously operating said switchin means and saidbraking means.

GEORGE W. JACKSON. WILLIAM P. CANNING.

